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1.
Artigo em Inglês | MEDLINE | ID: mdl-38587505

RESUMO

By investigating wet and dry age-related ripening of beef, Pseudomonas strains V3/3/4/13T and V3/K/3/5T were isolated. Strain V3/3/4/13T exhibited more than 99 % 16S rRNA gene-based similarity to Pseudomonas fragi and other members of this group, while isolate V3/K/3/5T was very close to Pseudomonas veronii and a number of relatives within the Pseudomonas fluorescens group. Additional comparisons of complete rpoB sequences and draft genomes allowed us to place isolate V3/3/4/13T close to Pseudomonas deceptionensis DSM 26521T. In the case of V3/K/3/5T the closest relative was P. veronii DSM 11331T. Average nucleotide identity (ANIb) and digital DNA-DNA hybridization (dDDH) values calculated from the draft genomes of V3/3/4/13T and P. deceptionensis DSM 26521T were 88.5 and 39.8 %, respectively. For V3/K/3/5T and its closest relative P. veronii DSM 11331T, the ANIb value was 95.1 % and the dDDH value was 60.7 %. The DNA G+C contents of V3/3/4/13T and V3/K/3/5T were 57.4 and 60.8 mol%, respectively. Predominant fatty acids were C16 : 0, C18 : 1 ω7c, C17 : 0 cyclo and summed feature C16 : 1 ω7ct/C15 : 0 iso 2OH. The main respiratory quinones were Q9, with minor proportions of Q8 and, in the case of V3/K/3/5T, additional Q10. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and, in the case of V3/K/3/5T, additional phosphatidylcholine. Based on the combined data, isolates V3/3/4/13T and V3/K/3/5T should be considered as representatives of two novel Pseudomonas species. The type strain of the newly proposed Pseudomonas kulmbachensis sp. nov. is V3/3/4/13T (=DSM 113654T=LMG 32520T), a second strain belonging to the same species is FLM 004-28 (=DSM 113604=LMG 32521); the type strain for the newly proposed Pseudomonas paraveronii sp. nov. is V3/K/3/5T (=DSM 113573T=LMG 32518T) with a second isolate FLM 11 (=DSM 113572=LMG 32519).


Assuntos
Galinhas , Ácidos Graxos , Animais , Bovinos , Composição de Bases , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Filogenia , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Pseudomonas/genética , Nucleotídeos
2.
FEMS Microbiol Ecol ; 100(5)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38520167

RESUMO

Coriariaceae are a small plant family of 14-17 species and subspecies that currently have a global but disjunct distribution. All species can form root nodules in symbiosis with diazotrophic Frankia cluster-2 strains, which form the earliest divergent symbiotic clade within this bacterial genus. Studies on Frankia cluster-2 mostly have focused on strains occurring in the northern hemisphere. Except for one strain from Papua New Guinea, namely Candidatus Frankia meridionalis Cppng1, no complete genome of Frankia associated with Coriaria occurring in the southern hemisphere has been published thus far, yet the majority of the Coriariaceae species occur here. We present field sampling data of novel Frankia cluster-2 strains, representing two novel species, which are associated with Coriaria arborea and Coriaria sarmentosa in New Zealand, and with Coriaria ruscifolia in Patagonia (Argentina), in addition to identifying Ca. F. meridionalis present in New Zealand. The novel Frankia species were found to be closely related to both Ca. F. meridionalis, and a Frankia species occurring in the Philippines, Taiwan, and Japan. Our data suggest that the different Frankia cluster-2 species diverged early after becoming symbiotic circa 100 million years ago.

3.
Microb Cell Fact ; 23(1): 29, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245756

RESUMO

BACKGROUND: Industrial by-products accrue in most agricultural or food-related production processes, but additional value chains have already been established for many of them. Crude glycerol has a 60% lower market value than commercial glucose, as large quantities are produced in the biodiesel industry, but its valorisation is still underutilized. Due to its high carbon content and the natural ability of many microorganisms to metabolise it, microbial upcycling is a suitable option for this waste product. RESULTS: In this work, the use of crude glycerol for the production of the value-added compound itaconate is demonstrated using the smut fungus Ustilago maydis. Starting with a highly engineered strain, itaconate production from an industrial glycerol waste stream was quickly established on a small scale, and the resulting yields were already competitive with processes using commercial sugars. Adaptive laboratory evolution resulted in an evolved strain with a 72% increased growth rate on glycerol. In the subsequent development and optimisation of a fed-batch process on a 1.5-2 L scale, the use of molasses, a side stream of sugar beet processing, eliminated the need for other expensive media components such as nitrogen or vitamins for biomass growth. The optimised process was scaled up to 150 L, achieving an overall titre of 72 g L- 1, a yield of 0.34 g g- 1, and a productivity of 0.54 g L- 1 h- 1. CONCLUSIONS: Pilot-scale itaconate production from the complementary waste streams molasses and glycerol has been successfully established. In addition to achieving competitive performance indicators, the proposed dual feedstock strategy offers lower process costs and carbon footprint for the production of bio-based itaconate.


Assuntos
Glicerol , Succinatos , Glicerol/metabolismo , Succinatos/metabolismo , Glucose/metabolismo
4.
Toxicon ; 237: 107556, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38072317

RESUMO

Cnidarians thriving in biofouling communities on aquaculture net pens represent a significant health risk for farmed finfish due to their stinging cells. The toxins coming into contact with the fish, during net cleaning, can adversely affect their behavior, welfare, and survival, with a particularly serious health risk for the gills, causing direct tissue damage such as formation of thrombi and increasing risks of secondary infections. The hydroid Ectopleura larynx is one of the most common fouling organisms in Northern Europe. However, despite its significant economic, environmental, and operational impact on finfish aquaculture, biological information on this species is scarce and its venom composition has never been investigated. In this study, we generated a whole transcriptome of E. larynx, and identified its putative expressed venom toxin proteins (predicted toxin proteins, not functionally characterized) based on in silico transcriptome annotation mining and protein sequence analysis. The results uncovered a broad and diverse repertoire of putative toxin proteins for this hydroid species. Its toxic arsenal appears to include a wide and complex selection of toxin proteins, covering a large panel of potential biological functions that play important roles in envenomation. The putative toxins identified in this species, such as neurotoxins, GTPase toxins, metalloprotease toxins, ion channel impairing toxins, hemorrhagic toxins, serine protease toxins, phospholipase toxins, pore-forming toxins, and multifunction toxins may cause various major deleterious effects in prey, predators, and competitors. These results provide valuable new insights into the venom composition of cnidarians, and venomous marine organisms in general, and offer new opportunities for further research into novel and valuable bioactive molecules for medicine, agronomics and biotechnology.


Assuntos
Incrustação Biológica , Hidrozoários , Toxinas Biológicas , Animais , Peçonhas , Proteínas , Transcriptoma
5.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37917135

RESUMO

Strain TÜ4103T was originally sampled from Java, Indonesia and deposited in the Tübingen strain collection under the name 'Streptomyces sp.'. The strain was found to be an antibiotic producer as strain TÜ4103T showed bioactivity against Gram-positive bacteria, such as Bacillus subtilis and Kocuria rhizophila in bioassays. Strain TÜ4103T showed 16S rRNA gene sequence similarity of 99.65 % to Kitasatospora cheerisanensis DSM 101999T and 98.82 % to Kitasatospora niigatensis DSM 44781T and Kitasatospora cineracea DSM 44780T. Genome-based phylogenetic analysis revealed that strain TÜ4103T is closely related to K. cineracea DSM 44780T and K. niigatensis DSM 44781T. The digital DNA-DNA hybridization values between the genome sequences of strain TÜ4103T and its closest phylogenomic relatives, strains DSM 44780T and DSM 44781T, were 43.0 and 42.9 %, respectively. Average nucleotide identity (ANI) values support this claim, with the highest ANI score of 91.14 % between TÜ4103T and K. niigatensis being closely followed by an ANI value of 91.10 % between K. cineracea and TÜ4103T. The genome of TÜ4103T has a size of 7.91 Mb with a G+C content of 74.05 mol%. Whole-cell hydrolysates of strain TÜ4103T are rich in meso-diaminopimelic acid, and rhamnose, galactose and mannose are characteristic as whole-cell sugars. The phospholipid profile contains phosphatidylethanolamine, diphosphatidylglycerol and glycophospholipid. The predominant menaquinones (>93.5 %) are MK-9(H8) and MK-9(H6). Based on the phenotypic, genotypic and genomic characteristics, strain TÜ4103T (=DSM 114396T=CECT 30712T) merits recognition as the type strain of a novel species of the genus Kitasatospora, for which the name Kitasatospora fiedleri sp. nov. is proposed.


Assuntos
Antibacterianos , Ácidos Graxos , Composição de Bases , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Ácidos Graxos/química , Nucleotídeos
6.
Chem Sci ; 14(46): 13463-13467, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38033887

RESUMO

Twenty oxygenated aristolochene congeners were rapidly synthesised by combining genes from four different fungal pathways in the fungal host organism Aspergillus oryzae. Compounds produced in a single step include the natural product hypoxylan A and an epimer of guignaderemophilane C. A new fungal aromatase was discovered that produces phenols by oxidative demethylation.

7.
OMICS ; 27(9): 434-443, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37707996

RESUMO

Systems biology tools offer new prospects for industrial strain selection. For bacteria that are significant for industrial applications, whole-genome sequencing coupled to flux balance analysis (FBA) can help unpack the complex relationships between genome mutations and carbon trafficking. This work investigates the l-tyrosine (l-Tyr) overproducing model system Corynebacterium glutamicum ATCC 21573 with an eye to more rational and precision strain development. Using genome-wide mutational analysis of C. glutamicum, we identified 27,611 single nucleotide polymorphisms and 479 insertion/deletion mutations. Mutations in the carbon uptake machinery have led to phosphotransferase system-independent routes as corroborated with FBA. Mutations within the central carbon metabolism of C. glutamicum impaired the carbon flux, as evidenced by the lower growth rate. The entry to and flow through the tricarboxylic acid cycle was affected by mutations in pyruvate and α-ketoglutarate dehydrogenase complexes, citrate synthase, and isocitrate dehydrogenase. FBA indicated that the estimated flux through the shikimate pathway became larger as the l-Tyr production rate increased. In addition, protocatechuate export was probabilistically impossible, which could have contributed to the l-Tyr accumulation. Interestingly, aroG and cg0975, which have received previous attention for aromatic amino acid overproduction, were not mutated. From the branch point molecule, prephenate, the change in the promoter region of pheA could be an influential contributor. In summary, we suggest that genome sequencing coupled with FBA is well poised to offer rational guidance for industrial strain development, as evidenced by these findings on carbon trafficking in C. glutamicum ATCC 21573.


Assuntos
Corynebacterium glutamicum , Corynebacterium glutamicum/genética , Mapeamento Cromossômico , Indústrias , Carbono
8.
Cell Rep Med ; 4(9): 101152, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37572667

RESUMO

Male sex represents one of the major risk factors for severe COVID-19 outcome. However, underlying mechanisms that mediate sex-dependent disease outcome are as yet unknown. Here, we identify the CYP19A1 gene encoding for the testosterone-to-estradiol metabolizing enzyme CYP19A1 (also known as aromatase) as a host factor that contributes to worsened disease outcome in SARS-CoV-2-infected males. We analyzed exome sequencing data obtained from a human COVID-19 cohort (n = 2,866) using a machine-learning approach and identify a CYP19A1-activity-increasing mutation to be associated with the development of severe disease in men but not women. We further analyzed human autopsy-derived lungs (n = 86) and detect increased pulmonary CYP19A1 expression at the time point of death in men compared with women. In the golden hamster model, we show that SARS-CoV-2 infection causes increased CYP19A1 expression in the lung that is associated with dysregulated plasma sex hormone levels and reduced long-term pulmonary function in males but not females. Treatment of SARS-CoV-2-infected hamsters with a clinically approved CYP19A1 inhibitor (letrozole) improves impaired lung function and supports recovery of imbalanced sex hormones specifically in males. Our study identifies CYP19A1 as a contributor to sex-specific SARS-CoV-2 disease outcome in males. Furthermore, inhibition of CYP19A1 by the clinically approved drug letrozole may furnish a new therapeutic strategy for individualized patient management and treatment.


Assuntos
Aromatase , COVID-19 , Feminino , Humanos , Masculino , Aromatase/genética , Letrozol , SARS-CoV-2 , COVID-19/genética , Estradiol , Testosterona
9.
Front Microbiol ; 13: 1032515, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439843

RESUMO

Research on biogas-producing microbial communities aims at elucidation of correlations and dependencies between the anaerobic digestion (AD) process and the corresponding microbiome composition in order to optimize the performance of the process and the biogas output. Previously, Lachnospiraceae species were frequently detected in mesophilic to moderately thermophilic biogas reactors. To analyze adaptive genome features of a representative Lachnospiraceae strain, Anaeropeptidivorans aminofermentans M3/9T was isolated from a mesophilic laboratory-scale biogas plant and its genome was sequenced and analyzed in detail. Strain M3/9T possesses a number of genes encoding enzymes for degradation of proteins, oligo- and dipeptides. Moreover, genes encoding enzymes participating in fermentation of amino acids released from peptide hydrolysis were also identified. Based on further findings obtained from metabolic pathway reconstruction, M3/9T was predicted to participate in acidogenesis within the AD process. To understand the genomic diversity between the biogas isolate M3/9T and closely related Anaerotignum type strains, genome sequence comparisons were performed. M3/9T harbors 1,693 strain-specific genes among others encoding different peptidases, a phosphotransferase system (PTS) for sugar uptake, but also proteins involved in extracellular solute binding and import, sporulation and flagellar biosynthesis. In order to determine the occurrence of M3/9T in other environments, large-scale fragment recruitments with the M3/9T genome as a template and publicly available metagenomes representing different environments was performed. The strain was detected in the intestine of mammals, being most abundant in goat feces, occasionally used as a substrate for biogas production.

10.
BMC Genomics ; 23(1): 602, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986253

RESUMO

It is currently assumed that around 100 million years ago, the common ancestor to the Fabales, Fagales, Rosales and Cucurbitales in Gondwana, developed a root nodule symbiosis with a nitrogen-fixing bacterium. The symbiotic trait evolved first in Frankia cluster-2; thus, strains belonging to this cluster are the best extant representatives of this original symbiont. Most cluster-2 strains could not be cultured to date, except for Frankia coriariae, and therefore many aspects of the symbiosis are still elusive. Based on phylogenetics of cluster-2 metagenome-assembled genomes (MAGs), it has been shown that the genomes of strains originating in Eurasia are highly conserved. These MAGs are more closely related to Frankia cluster-2 in North America than to the single genome available thus far from the southern hemisphere, i.e., from Papua New Guinea.To unravel more biodiversity within Frankia cluster-2 and predict routes of dispersal from Gondwana, we sequenced and analysed the MAGs of Frankia cluster-2 from Coriaria japonica and Coriaria intermedia growing in Japan, Taiwan and the Philippines. Phylogenetic analyses indicate there is a clear split within Frankia cluster-2, separating a continental from an island lineage. Presumably, these lineages already diverged in Gondwana.Based on fossil data on the host plants, we propose that these two lineages dispersed via at least two routes. While the continental lineage reached Eurasia together with their host plants via the Indian subcontinent, the island lineage spread towards Japan with an unknown host plant.


Assuntos
Frankia , Magnoliopsida , Frankia/genética , Magnoliopsida/genética , Metagenoma , Fixação de Nitrogênio , Filogenia , Plantas/genética , Simbiose/genética
11.
J Fungi (Basel) ; 8(8)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36012850

RESUMO

The gilled mushroom Clitopilus passeckerianus (Entolomataceae, Agaricales, Basidiomycota) is well known to produce the terpenoid pleuromutilin, which is the biotechnological basis for medically important antibiotics such as lefamulin and retapamulin. Their unique mode of action and good tolerance entails an increasing demand of pleuromutilin-derived antibiotics in veterinary and human health care. Surprisingly, despite their pharmaceutical importance, no genome sequence is available of any pleuromutilin-producing fungus. Here, we present the high-quality draft genome sequence of the pleuromutilin-producer C. passeckerianus DSM1602 including functional genome annotation. More precisely, we employed a hybrid assembly strategy combining Illumina sequencing and Nanopore sequencing to assemble the mitochondrial genome as well as the nuclear genome. In accordance with the dikaryotic state of the fungus, the nuclear genome has a diploid character. Interestingly, the mitochondrial genome appears duplicated. Bioinformatic analysis revealed a versatile secondary metabolism with an emphasis on terpenoid biosynthetic enzymes in C. passeckerianus and also in related strains. Two alleles of biosynthetic gene clusters for pleuromutilin were found in the genome of C. passeckerianus. The pleuromutilin genes were reassembled with yeast-specific elements for heterologous expression in Saccharomyces cerevisiae. Our work lays the foundation for metabolic strain engineering towards higher yields of the valuable compound pleuromutilin.

12.
Front Plant Sci ; 13: 894985, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968096

RESUMO

Pseudomonas sp. strain 1008 was isolated from the rhizosphere of field grown wheat plants at the tillering stage in an agricultural plot near Pergamino city, Argentina. Based on its in vitro phosphate solubilizing capacity and the production of IAA, strain 1008 was formulated as an inoculant for bacterization of wheat seeds and subjected to multiple field assays within the period 2010-2017. Pseudomonas sp. strain 1008 showed a robust positive impact on the grain yield (+8% on average) across a number of campaigns, soil properties, seed genotypes, and with no significant influence of the simultaneous seed treatment with a fungicide, strongly supporting the use of this biostimulant bacterium as an agricultural input for promoting the yield of wheat. Full genome sequencing revealed that strain 1008 has the capacity to access a number of sources of inorganic and organic phosphorus, to compete for iron scavenging, to produce auxin, 2,3-butanediol and acetoin, and to metabolize GABA. Additionally, the genome of strain 1008 harbors several loci related to rhizosphere competitiveness, but it is devoid of biosynthetic gene clusters for production of typical secondary metabolites of biocontrol representatives of the Pseudomonas genus. Finally, the phylogenomic, phenotypic, and chemotaxonomic comparative analysis of strain 1008 with related taxa strongly suggests that this wheat rhizospheric biostimulant isolate is a representative of a novel species within the genus Pseudomonas, for which the name Pseudomonas pergaminensis sp. nov. (type strain 1008T = DSM 113453T = ATCC TSD-287T) is proposed.

13.
NAR Genom Bioinform ; 4(3): lqac055, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35855324

RESUMO

Today, one of the biggest challenges in antibiotic research is a targeted prioritization of natural compound producer strains and an efficient dereplication process to avoid undesired rediscovery of already known substances. Thereby, genome sequence-driven mining strategies are often superior to wet-lab experiments because they are generally faster and less resource-intensive. In the current study, we report on the development of a novel in silico screening approach to evaluate the genetic potential of bacterial strains to produce protein synthesis inhibitors (PSI), which was termed the protein synthesis inhibitor ('psi') target gene footprinting approach = Ψ-footprinting. The strategy is based on the occurrence of protein synthesis associated self-resistance genes in genome sequences of natural compound producers. The screening approach was applied to 406 genome sequences of actinomycetes strains from the DSMZ strain collection, resulting in the prioritization of 15 potential PSI producer strains. For twelve of them, extract samples showed protein synthesis inhibitory properties in in vitro transcription/translation assays. For four strains, namely Saccharopolyspora flava DSM 44771, Micromonospora aurantiaca DSM 43813, Nocardioides albertanoniae DSM 25218, and Geodermatophilus nigrescens DSM 45408, the protein synthesis inhibitory substance amicoumacin was identified by HPLC-MS analysis, which proved the functionality of the in silico screening approach.

14.
J Fungi (Basel) ; 8(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35628779

RESUMO

Ustilago maydis is an important plant pathogen that causes corn smut disease and serves as an effective biotechnological production host. The lack of a comprehensive metabolic overview hinders a full understanding of the organism's environmental adaptation and a full use of its metabolic potential. Here, we report the first genome-scale metabolic model (GSMM) of Ustilago maydis (iUma22) for the simulation of metabolic activities. iUma22 was reconstructed from sequencing and annotation using PathwayTools, and the biomass equation was derived from literature values and from the codon composition. The final model contains over 25% annotated genes (6909) in the sequenced genome. Substrate utilization was corrected by BIOLOG phenotype arrays, and exponential batch cultivations were used to test growth predictions. The growth data revealed a decrease in glucose uptake rate with rising glucose concentration. A pangenome of four different U. maydis strains highlighted missing metabolic pathways in iUma22. The new model allows for studies of metabolic adaptations to different environmental niches as well as for biotechnological applications.

15.
J Fungi (Basel) ; 8(3)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35330271

RESUMO

The family of Ustilaginaceae belongs to the order of Basidiomycetes. Despite their plant pathogenicity causing, e.g., corn smut disease, they are also known as natural producers of value-added chemicals such as extracellular glycolipids, organic acids, and polyols. Here, we present 17 high-quality draft genome sequences (N50 > 1 Mb) combining third-generation nanopore and second-generation Illumina sequencing. The data were analyzed with taxonomical genome-based bioinformatics methods such as Percentage of Conserved Proteins (POCP), Average Nucleotide Identity (ANI), and Average Amino Acid Identity (AAI) analyses indicating that a reclassification of the Ustilaginaceae family might be required. Further, conserved core genes were determined to calculate a phylogenomic core genome tree of the Ustilaginaceae that also supported the results of the other phylogenomic analysis. In addition, to genomic comparisons, secondary metabolite clusters (e.g., itaconic acid, mannosylerythritol lipids, and ustilagic acid) of biotechnological interest were analyzed, whereas the sheer number of clusters did not differ much between species.

16.
Sci Rep ; 12(1): 2666, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177693

RESUMO

The continuing reports of plastic pollution in various ecosystems highlight the threat posed by the ever-increasing consumption of synthetic polymers. Therefore, Pseudomonas capeferrum TDA1, a strain recently isolated from a plastic dump site, was examined further regarding its ability to degrade polyurethane (PU) compounds. The previously reported degradation pathway for 2,4-toluene diamine, a precursor and degradation intermediate of PU, could be confirmed by RNA-seq in this organism. In addition, different cell fractions of cells grown on a PU oligomer were tested for extracellular hydrolytic activity using a standard assay. Strikingly, purified outer membrane vesicles (OMV) of P. capeferrum TDA1 grown on a PU oligomer showed higher esterase activity than cell pellets. Hydrolases in the OMV fraction possibly involved in extracellular PU degradation were identified by mass spectrometry. On this basis, we propose a model for extracellular degradation of polyester-based PUs by P. capeferrum TDA1 involving the role of OMVs in synthetic polymer degradation.


Assuntos
Fenilenodiaminas/metabolismo , Poliuretanos/metabolismo , Pseudomonas/metabolismo , Biodegradação Ambiental
17.
Microorganisms ; 10(2)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35208823

RESUMO

The microbial biogas network is complex and intertwined, and therefore relatively stable in its overall functionality. However, if key functional groups of microorganisms are affected by biotic or abiotic factors, the entire efficacy may be impaired. Bacteriophages are hypothesized to alter the steering process of the microbial network. In this study, an enriched fraction of virus-like particles was extracted from a mesophilic biogas reactor and sequenced on the Illumina MiSeq and Nanopore GridION sequencing platforms. Metagenome data analysis resulted in identifying 375 metagenome-assembled viral genomes (MAVGs). Two-thirds of the classified sequences were only assigned to the superkingdom Viruses and the remaining third to the family Siphoviridae, followed by Myoviridae, Podoviridae, Tectiviridae, and Inoviridae. The metavirome showed a close relationship to the phage genomes that infect members of the classes Clostridia and Bacilli. Using publicly available biogas metagenomic data, a fragment recruitment approach showed the widespread distribution of the MAVGs studied in other biogas microbiomes. In particular, phage sequences from mesophilic microbiomes were highly similar to the phage sequences of this study. Accordingly, the virus particle enrichment approach and metavirome sequencing provided additional genome sequence information for novel virome members, thus expanding the current knowledge of viral genetic diversity in biogas reactors.

18.
Appl Environ Microbiol ; 88(6): e0251021, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35108081

RESUMO

Endophytic fungi have been recognized as prolific producers of chemically diverse secondary metabolites. In this work, we describe a new representative of the order Helotiales isolated from the medicinal plant Bergenia pacumbis. Several bioactive secondary metabolites were produced by this Helotiales sp. BL 73 isolate grown on rice medium, including cochlioquinones and isofusidienols. Sequencing and analysis of the approximately 59-Mb genome revealed at least 77 secondary metabolite biosynthesis gene clusters, of which several could be associated with detected compounds or linked to previously reported molecules. Four terpene synthase genes identified in the BL73 genome were codon optimized and expressed, together with farnesyl-, geranyl-, and geranylgeranyl-pyrophosphate synthases, in Streptomyces spp. An analysis of recombinant strains revealed the production of linalool and its oxidized form, terpenoids typically associated with plants, as well as a yet unidentified terpenoid. This study demonstrates the importance of a complex approach to the investigation of the biosynthetic potential of endophytic fungi using both conventional methods and genome mining. IMPORTANCE Endophytic fungi represent an as yet underexplored source of secondary metabolites, of which some may have industrial and medical applications. We isolated a slow-growing fungus belonging to the order Helotiales from the traditional medicinal plant Bergenia pacumbis and characterized its potential to biosynthesize secondary metabolites. We used cultivation of the isolate with a subsequent analysis of compounds produced, bioinformatics-based mining of the genome, and heterologous expression of several terpene synthase genes. Our study revealed that this Helotiales isolate has enormous potential to produce structurally diverse natural products, including polyketides, nonribosomally synthesized peptides, terpenoids, and ribosomally synthesized and posttranslationally modified peptides (RiPPs). Identification of meroterpenoids and xanthones, along with establishing a link between these molecules and their putative biosynthetic genes, sets the stage for investigation of the respective biosynthetic pathways. The heterologous production of terpenoids suggests that this approach can be used for the discovery of new compounds belonging to this chemical class using Streptomyces bacteria as hosts.


Assuntos
Ascomicetos , Streptomyces , Ascomicetos/genética , Vias Biossintéticas/genética , Família Multigênica , Metabolismo Secundário , Streptomyces/genética
19.
Int J Syst Evol Microbiol ; 72(12)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36748496

RESUMO

An anaerobic bacterial strain, designated strain M3/9T, was isolated from a laboratory-scale biogas fermenter fed with maize silage supplemented with 5 % wheat straw. Cells were straight, non-motile rods, which stained Gram-negative. Optimal growth occurred between 30 and 40°C, at pH 7.5-8.5, and up to 3.9 % (w/v) NaCl was tolerated. When grown on peptone from casein and soymeal, strain M3/9T produced mainly acetic acid, ethanol, and isobutyric acid. The major cellular fatty acids of the novel strain were C16 : 0 and C16 : 0 DMA. The genome of strain M3/9T is 3757  330 bp in size with a G+C content of 38.45 mol%. Phylogenetic analysis allocated strain M3/9T within the family Lachnospiraceae with Clostridium colinum DSM 6011T and Anaerotignum lactatifermentans DSM 14214T being the most closely related species sharing 57.86 and 56.99% average amino acid identity and 16S rRNA gene sequence similarities of 91.58 and 91.26 %, respectively. Based on physiological, chemotaxonomic and genetic data, we propose the description of a novel species and genus Anaeropeptidivorans aminofermentans gen. nov., sp. nov., represented by the type strain M3/9T (=DSM 100058T=LMG 29527T). In addition, an emended description of Clostridium colinum is provided.


Assuntos
Biocombustíveis , Ácidos Graxos , Filogenia , RNA Ribossômico 16S/genética , Ácidos Graxos/química , Composição de Bases , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Análise de Sequência de DNA , Clostridium/genética
20.
Int J Syst Evol Microbiol ; 72(12)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36748598

RESUMO

An actinobacterial strain, CMB-FB, was isolated from surface-sterilized root nodules of a Coriaria intermedia plant growing along Halsema Highway in the province of Benguet (Luzon, Philippines). The 16S rRNA gene sequence of CMB-FB showed high sequence similarity to those of the type strains of Streptomyces rishiriensis (99.4 %), Streptomyces humidus (99.1 %), Streptomyces cacaoi subsp. asoensis (99.0 %), and Streptomyces phaeofaciens (98.6 %). The major menaquinones of CMB-FB were composed of MK-9(H4), MK-9(H6) and MK-9(H8), and there was a minor contribution of MK-9(H10). The polar lipid profile consisted of phosphatidylethanolamine, unidentified aminolipids and phospholipids, a glycophospholipid and four unidentified lipids. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid. The major fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The results of physiological analysis indicated that CMB-FB was mesophilic. The results of phylogenetic, genome-genome distance calculation and average nucleotide identity analysis indicated that the isolated strain represents the type strain of a novel species. On the basis of these results, strain CMB-FB (=DSM 112754T=LMG 32457T) is proposed as the type strain of the novel species Streptomyces coriariae sp. nov.


Assuntos
Ácidos Graxos , Streptomyces , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Filipinas , Fosfolipídeos/química , Vitamina K 2/química
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